PostgreSQL General Information

 Main PostgreSQL features: 

        - inheritance
        - data types
        - functions
        - constraints
        - triggers
        - rules
        - transactional integrity


History of PostgreSQL: 

The original Postgres code was the effort of many people working under the direction 
of Professor Michael Stonebraker at the University of California, Berkeley.
PostgreSQL documentation can be found via the PostgreSQL WWW home page at:
                        http://www.PostgreSQL.org 

The latest release is version 7.2.2 and major releases is going to be every four months.

 PostgreSQL vs MySql 
In comparison to MySQL, PostgreSQL is slower on inserts/updates because of transaction overhead. 
See web page comparing PostgreSQL to MySQL at http://openacs.org/why-not-mysql.html


FAQ:

 What languages are available to communicate with PostgreSQL? 

                C (libpq) 
                C++ (libpq++) 
                Embedded C (ecpg) 
                Java (jdbc) 
                Perl (perl5) 
                ODBC (odbc) 
                Python (PyGreSQL) 
                TCL (libpgtcl) 
                C Easy API (libpgeasy) 
                Embedded HTML 

 What is the maximum size for a row, a table, and a database in PostgreSQL? 
                                These are the limits:
        Maximum size for a database?             unlimited (1 TB databases exist)
        Maximum size for a table?                16 TB
        Maximum size for a row?                  1.6TB
        Maximum size for a field?                1 GB
        Maximum number of rows in a table?       unlimited
        Maximum number of columns in a table?    250-1600 depending on column types
        Maximum number of indexes on a table?    unlimited

   Of course, these are not actually unlimited, but limited to available disk space and 
   memory/swap space. Performance may suffer when these values get unusually large. 
   The maximum table size of 16 TB does not require large file support from the operating system. 
   Large tables are stored as multiple 1 GB files so file system size limits are not important.

   The maximum table size and maximum number of columns can be increased if the default block 
   size is increased to 32k.

 How to perform queries using multiple databases? 
        There is no way to query any database except the current one, because PostgreSQL loads 
        database-specific system catalogs, it is uncertain how a cross-database query should even behave.

 Does PostgreSQL have a graphical user interface? A report generator? 
        Graphical user interface called pgaccess is shipped as part of the distribution. 
        pgaccess also has a report generator. 
        The Web page is http://www.flex.ro/pgaccess

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Last Modified  September 19, 2002